Biological waste
Guidance on how to package, treat, label, store and dispose of biological waste on the St. George campus, including what constitutes biological waste and how to request service or support.
Who must follow these procedures
All laboratories that manipulate potentially hazardous biological agents and materials and generate waste containing such agents are responsible for separating, packaging and treating their laboratory waste before its removal and disposal.
These procedures apply to waste contaminated with or containing biological agents only.
If your lab waste is contaminated with chemical and/or radioactive materials, follow the procedure for mixed waste.
If your lab waste contains sharp or pointy objects, follow the procedure for sharp waste.
Biological Containment Level 2 labs
These biological waste procedures apply to any laboratory producing needles and Biological Containment Level 2 or greater laboratories.
Biological Containment Level 1 labs
Biological Containment Level 1 labs are to handle their waste as non-hazardous (except if they generate needles or their Risk Group 1 biowaste contains chemical or radiation hazards). To request garbage bags for non-hazardous waste, contact the Caretaking team.
A Containment Level 1 lab must autoclave and/or chemically treat their Risk Group 1 biowaste before disposal if it is genetically modified material and/or non-native.
This normally requires autoclaving because of Environment Canada regulations. Labs must use autoclave bags that do not have the biohazard warning symbol supplied by MedStores for their genetically modified material and/or non-native Risk Group 1 biowaste.
What is biological waste?
Biological waste includes:
- Liquids such as used cell culturing media, supernatant, blood or blood fractions (serum), etc., which contain viable biological agents
- Materials considered pathological, including any part of the human body, tissues and bodily fluids, but excluding fluids, extracted teeth, hair, nail clippings, and the like that are not infectious
- Any part of an animal infected [or suspected to be infected] with a communicable disease
- Non-sharp, solid laboratory waste (empty plastic cell culture flasks and petri dishes, empty plastic tubes, gloves, wrappers, absorbent tissues, etc.) which may be, or is known to be, contaminated with viable biological agents
- All sharp and pointed items used in medical care, diagnosis, and research, including the manipulation and care of laboratory animals, which should be considered potentially infectious
- Laboratory glassware that is known or suspected to be contaminated with hazardous biological agents
Packaging and treatment
Materials contaminated with hazardous biological agents must be collected in the appropriate containers and sterilized or disinfected before disposal.
In addition to the general packaging requirements outlined in Section 4, the specific requirements below for biological waste must be followed.
Collect liquids in leak-proof containers such as flasks or bottles.
Liquid waste containers designed to withstand autoclaving temperatures must be used when steam sterilization is used to treat the biohazardous liquid. To allow pressure equalization, they must not be sealed.
Non-sharp, solid laboratory waste (empty plastic cell culture flasks and petri dishes, agar plates, empty plastic tubes, gloves, wrappers, absorbent tissues, etc.), which may be, or is known to be, contaminated with viable biological agents, should be collected in a yellow bio waste plastic 20-litre pail. These plastic pails display the biohazard warning symbol.
To request these pails, please contact the Environmental Protection Services team.
For laboratories generating large volumes of risk group 1 agar gel in disposable petri dishes and tubes requiring sterilization:
Such waste should be double bagged in autoclave bags that do not have the biohazardous warning symbol. The bags should be put into an autoclavable pan or basin during the autoclave process. This will contain any agar that leaks from the bags during sterilization.
Any waste that has been autoclaved in Autoclave bags at the university must be double bagged, twist-tied or taped shut. Both the biosafety certificate number and room number must be marked visibly on them before they can be collected.
When necessary or for safety reasons, inactivate the biological agents by using either chemical disinfection or steam sterilization procedures.
Although chemical disinfectants play a useful role in many situations where decontamination is required, when they are used to sterilize waste, the principal investigator must assure the U of T Institutional Biosafety and Biosecurity Committee that the routines and methods achieve the desired objective. See bleach as a disinfectant.
Autoclaving (steam sterilization) is the preferred (and generally regarded as the most reliable) method of sterilizing biological waste. Depending on the volume of waste to be sterilized, it may be necessary to extend the duration of exposure to high-temperature steam under pressure.
Steam sterilization is not recommended for laboratory waste contaminated with or containing a combination of viable biological agents and significant amounts of hazardous chemical or radioactive materials. Consult Section 5.4 for procedures.
Containers of liquid waste must be placed into an autoclavable tray or pan of sufficient capacity to contain all liquid in the event of vessel failure or breakage inside the autoclave chamber. Use extreme caution when handling autoclaved liquids since they are hot and may boil over.
Autoclavable bags of solid waste should be closed but not sealed airtight to allow steam penetration before they are placed into the autoclave chamber. After autoclaving and cooling, these bags of autoclaved waste must be double bagged, twist-tied or taped shut and both the biosafety certificate number and room number marked visibly on them.
Never autoclave yellow bio waste plastic 20-litre pails as it will damage the autoclave and ruin the integrity of the pail.
Labeling
To be collected, all filled yellow bio waste plastic 20-litre pails must have legibly and accurately written on the pail lid:
- The lab’s biosafety certificate number
- The lab’s room number
To be collected, all filled bio waste bags must have legibly and accurately written on the side:
- The lab’s biosafety certificate number
- The lab’s room number
Storage and disposal
Following steam sterilization or chemical disinfection, innocuous liquids may be disposed of via the laboratory drainage system. Flush with enough clean water to purge the drain immediately after disposal of all liquids.
Hazardous chemicals and radioisotopes must not be disposed of in this manner!
Do not pour melted agar into the sink or floor drains. Allow it to cool and solidify for disposal as bio waste unless produced in a Containment Level 1 lab, where it can be placed with non-hazardous waste. However, Containment Level 1 labs should use autoclave bags that do not have the biohazardous warning symbol. These autoclave bags are available from Medstores.
Biowaste collection schedule
Special pick-up and disposal of untreated biological laboratory waste
U of T has negotiated a contract with a commercial firm licensed to remove and transport biologically contaminated laboratory waste to a designated disposal site for steam sterilization and shredding.
Environmental protection technicians collect directly from the labs; therefore, don’t leave pails in hallways or corridors. They should be kept in your lab until collected.
Ensure all information on the biowaste container is completed, or the pail will not be collected.
Getting support
If you have questions, please contact the Environmental Protection Services team.
For more information about procedures for biological labs, you can also visit the U of T biosafety program website.